Rollers are generally used with commercial lawn mowers of the type that include cutting reels. The rollers are provided for supporting the cutting reel a predetermined distance above the ground to thereby position the cutting reel for cutting the grass to a desired length. Typically, the rollers are positioned either before or after the cutting reel of the lawn mower. Rollers that are positioned after the cutting reel usually have a tubular construction with the outer surface of the tubular roller being smooth for laying flat the cut grass.
Rollers that are positioned before the cutting reel, referred to herein as "groove-type rollers," are generally constructed with grooves and include a contacting edge for contacting the ground. The grooves are provided to minimize the amount of grass that is laid flat prior to cutting and, thereby, provide a more even cut.
The contacting edges of prior art groove-type rollers extend outward from the roller. These edges are typically thin and have sides that oppose one another. As a result, these prior art rollers have the tendency to pick up debris such as acorns, pinecones, small stones, and other small objects that may be in the turf. Since the sides of the extending edges oppose one another, the debris becomes jammed in the roller mechanism. To maintain the rollers operational, the operator is required to periodically remove the debris from the opposing sides of the roller. The debris can sometimes be removed manually, however, many times the operator must use a device specially constructed for removing debris from the rollers.
Additionally, these prior art groove-type rollers are often made from a mild steel or other soft metal. As a result, the contacting edges of these rollers tend to flatten when impacted by hard objects such as roots, stones, hard surfaces, or other objects that are harder than the metal. Such flattening is typically referred to as "mushrooming" since the contacting surface tends to take on the shape of a mushroom. The mushrooming of these prior art groove-type rollers increases the tendency of these rollers to pick up stones and makes it more difficult to dislodge the stones. Further, the mushrooming effect detracts from the effectiveness of the roller and decreases its life span.
Still further, prior art groove-type rollers such as those described above tend to dig in and cut up the turf when the mower is turning with the cutting reel engaged. Essentially, the contacting edges of the groove-type rollers act as plows that ruin the ground upon which the grass is growing. The tendency of these prior art groove-type rollers to dig up the ground is increased with the mushrooming effect described above. To prevent such a result, the mowers that employ these prior art groove-type rollers have been used to cut grass in straight lines only. When the mower needs to be turned, it must be driven off of the grass area, the cutting reel must be disengaged and/or lifted, the mower must be turned around, the mower must then be driven back to the grass area, and the roller and cutting reels are lowered and/or reengaged.
Still other prior art groove-type rollers have been constructed with a variety of component parts. These components require constant application of large amounts of grease, or other friction-reducing elements. The grease is applied to the end of the roller for the purpose of reducing friction among the component parts. Grease has also been used in combination with prior art rollers to reduce rusting and thereby increase the life span of the roller. However, the use of grease increases the tendency of the roller to accumulate dirt and other organic matter that decreases from the efficiency of the roller. The accumulation of dirt and other organic matter further adds to the tendency of these rollers to pick up small stones, as discussed above. Still further, the use of grease is undesirable because it tends to escape to the grass and eventually the environment.
Furthermore, the construction of prior art groove-type rollers is such that when the roller comes into contact with large obstacles such as tree roots, cart paths, rocks, or other large obstacles, a mounting portion of the roller that interfaces the roller with the mower tends to become bent, thereby causing the roller to become bent. Furthermore, shifting of the mounting portion interfacing the roller with the mower in itself can cause a flexing of the roller that temporarily or permanently affects the ability of the roller to stand up the grass for cutting. The bending condition causes the groove-type roller to wear faster, creates an uneven cutting of the grass, and a plowing effect that disturbs the lay of the ground and turf as is discussed above.
Accordingly, it is desirable to provide a groove-type roller for use with a commercial type lawn mower of the type that includes cutting reels wherein the lifting mower avoids the foregoing disadvantages of the prior art.